Dinoflagellates are a long stringy sticky nightmare with air bubbles. They are toxic and come in a variety of colours. If you have Dino, you must closely monitor your water chemistry and perform regular water change. This is one of the hardest algae to control. Dino can be the result of overfeeding and incorrect dosing or excess proteins in your water from inadequate skimming.
No one method has proven 100% effective against Dino. Limiting phosphates will certainly help and using natural methods to target the cause of the algae problem will always prove best. Production of Macro Algae to combat the Dino is recommended.
That being said at eQuaria we have found that regular dosing with Kalkwasser (yes we sell it) can eliminate this sticky little bugger and keep it away in more than 90% of cases. Kalkwasser will stabilize your alkalinity and boost your calcium. The more the use the higher your pH will go.
pH Stabilization for marine systems.
If you are infected with Dinoflagellates, raise your pH to around 8.6 with Kalkwasser for a short time (a few days) and it should die. Normal marine system pH should be around 8.4 so return to this level after treatment.
Another method which has worked previously has been to black out the tank for three full days to starve the algae of light. Dose hydrogen peroxide into the system at the rate of 1ml per 38 litres of aquarium water per day.